Software-defined networking SDN allows network administrators to manage network services through abstraction of higher-level functionality. In a SDN network a system making decisions about where data traffic is to be sent is decoupled from an underlying data plane for forwarding the data traffic to a selected destination. A SDN network uses a predetermined protocol which enables the control plane to communicate with the underlying data plane. Examples of protocols used in the SDN network are the NETCONF, RESTCONF or the OpenFlow communication protocol.
The OpenFlow protocol enables network controllers to determine a path of transporting network packets across a network of switches. The OpenFlow protocol is layered on top of a transmission control protocol TCP and prescribes the use of transport layer security TLS. For transporting data traffic, a data plane of a transport network can be used. For instance, an optical transport network OTN based on wavelength division multiplexing can be implemented to transport data traffic via network nodes by traffic switching of optical data units ODUs.
Accordingly, there is a need to use the SDN resources of the optical transport network without any data loss efficiently to avoid unused OTN resources.